1. Field of the Invention
The present invention relates to apparatus used in pouring molten metals in casting applications, and more particularly, to a ladle gate for use with a ladle to control flow of molten metal, such as lead alloy, from the ladle and to prevent the formation of solidified drippage adjacent the ladle spouts.
2. Description of the Prior Art
In the molding of articles such as battery plates or grids, molten lead or lead alloy is poured into a mold having a narrow, generally planar mold cavity. The mold is generally positioned beneath a ladle which comprises an elongated trough-like structure and which includes a generally vertical front wall having a plurality of ports or pouring spouts extending along its length in horizontal alignment. The ladle is supported for pivotable movement about a longitudinal horizontal axis oriented such that the ladle can pivot forwardly and molten lead alloy can pour through the spouts into the mold. Molten lead alloy is supplied to the ladle such that when the ladle is in the static position, the level of the molten lead is maintained at a level slightly below the spouts and when the ladle pivots forwardly about its horizontal axis, the molten lead will then flow through the spouts.
Conventional lead alloys containing such additives as antimony, for example, have been used successfully with such apparatus and without difficulty. The formation of drippage or solidified lead at the lips of the spouts at the completion of each pouring cycle is controlled by directing gas flames at the spouts along the length of the ladle. However, lead alloys which have been used more recently in forming battery grids and which contain material such as strontium, have presented molding difficulties, in that, during the termination of the pouring cycles, as the flow of lead alloy through the ports ceases, some of the lead alloy tends to solidify and form drippage at the ladle spouts, and conventional means of controlling such solidified drippage is ineffective. The presence of such drippage is unacceptable since it may fall into an open mold thereby either preventing the mold from closing or contaminating the next article molded.